Status binaryInsert(int va[],int length,int size,int e)
{
	int low = 0;
	int high = length - 1;
	int middle = (low + high) / 2;

	if(length >= size)
		return ERROR;
	while(low < high)
	{
		if(e < va[middle])
			high = middle - 1;
		else if(e > va[middle])
			low = middle + 1;
		else
			return EXISTED;
		middle = (low + high) / 2;
	}

	t = low;
	for(i = length;i > t;i--)
		a[i] = a[i - 1];
	va[t] = e;
}
